In a former chapter we shewed, that this act of reiteration is the instrument employed by Nature for cultivating the powers of the mind as well as for communicating and impressing knowledge;—and we have also shewn that Nature in that process was successfully imitated by means of the catechetical exercise. This exercise has accordingly been found as powerful and efficient in promoting this, her second object, as it is in the first. The success of the catechetical exercise in communicating knowledge clearly to the young, even when it is but imperfectly managed, has been extensive and uniform; but wherever its nature has been properly understood, and it has been scientifically conducted, the amount of knowledge communicated in a given time, and with a given amount of mental and physical labour, stands confessedly without a parallel in the previous history of education. Minds the most obtuse, habits of listlessness the most inveterate, and mental imbecility, bordering on idiotcy, have been powerfully assailed and overcome; and knowledge, by means of this exercise, has forced its way, and firmly secured a place for itself, in minds which previously were little more than a blank.

The causes of its success in cultivating the powers of the mind were formerly explained; but its adaptation to the communicating of knowledge is still more peculiarly striking. We shall endeavour to point out a few of these peculiarities.

Let us for that purpose suppose a teacher desirous of communicating to a child the important fact, that "God at first made all things of nothing to shew his greatness;" it must be done, either by the child reading or hearing the sentence. If it be read, there is at least a chance, that the words may be all decyphered, and audibly pronounced, while the ideas contained in them have not yet reached the mind. The child may have carefully examined each word as it occurred, and may have reiterated each of them on his mind as he read them, and yet there may not be the slightest addition to his knowledge. The reiteration of words, as we have before explained, is not that which Nature requires, but the reiteration of ideas; and although we may, by substituting the one for the other, deceive ourselves, Nature will not be deceived; for unless the ideas contained in the sentence be reiterated by the mind, there can be no additional information conveyed.—The same thing may happen, if the words, instead of being read by the child, are announced by the teacher. The pupil may in that case hear the sounds; nay, he may repeat the words, and thus reiterate them in his mind after the teacher; but if he has not translated the words into their proper ideas as he proceeded, experience proves, that his knowledge remains as limited as before;—there has been no additional information. These cases are so common, and so uniform, that no farther illustration we think needs be given of them.

The desideratum in both these cases is, some exercise by which the child shall be compelled to translate the words into their several ideas; and by reiterating the ideas themselves, not the words which convey them, he shall be enabled at once to commit them to the keeping of the memory, and thus make them part of his knowledge. The catechetical exercise supplies this want. For if, in either case, after the words have been read or repeated, the child is asked, "What did God make?" the translation of the words into the ideas, if previously neglected, is now forced upon him, because without this it is impossible for him to prepare the answer. The ideas must be drawn from the words, and reiterated by the mind, independently of the words, before the exercise can be completed. And not only must the particular idea which answers the question be extracted, but the whole of the ideas contained in the sentence must be reiterated by the mind, before the selection can be begun, and the choice made. It is also specially worthy of remark, that even in such a case as this, where, on the sentence being read or heard, the words alone were at first perceived, yet no sooner does the mind proceed to its legitimate object, the reiteration of the ideas which the words convey, than the words themselves are instantly lost sight of, and in one sense are never again thought of. As soon as the kernel is extracted, the shell has lost its value. The pupil having once got sight of the ideas, tenaciously keeps hold of them, and never once thinks again of the words, which were merely the instrument employed by Nature to convey them. When the question is asked, and he answers it, the process consists in his translating the words of the whole sentence into their several ideas, chusing out the idea which answers the question from all the others, and then in clothing that idea in words which are now entirely his own.

In all this there is a long and intricate series of mental exercises, in every one of which the mind is actively employed, and it is in this, as before explained, that the value of this exercise, in cultivating the powers of the mind, really consists. But our present business is with the acquisition of knowledge by its means; and we have to observe, that in each of the mental operations required for the answer of a single question, the ideas contained in the original sentence have repeatedly to undergo the process of reiteration; by which they are more clearly perceived, and more permanently fixed on the memory, than they otherwise could have been. Hence the value of this exercise, even in those cases where the original sentence has been at the first fully understood. This will appear obvious by tracing the mental operation of the pupil from the beginning, when he has to answer the question.

There is first the understanding of the question asked at him. This must be heard and reiterated by the mind before its purport can be perceived, and all this before he can commence the proper mental operation upon the original sentence from which his answer is to be selected. He has then to review the words of the original sentence, still sounding in his ears, and to translate them into their several ideas, before he can begin to select the one required. Then comes the act of selection, having to chuse out from among all the others the special idea required as his answer; and lastly, there is the clothing of that idea in words suitable for the occasion, and the audibly pronouncing of these words as the answer required. The rapidity with which the mind passes from one part of this exercise to another, may prevent these several operations from being perceived, but it is not the less true that they must have taken place. And hence arises the value of the catechetical exercise, not only in cultivating in an extraordinary degree the mental faculties of the pupil, but in powerfully forcing information upon the mind, and permanently fixing it upon the memory for after use.

But even this does not exhaust the catalogue of benefits to be derived from the use of the catechetical exercise in communicating knowledge to the young. We have supposed only one question to have been asked by the teacher upon the original sentence, and yet we have seen that this one question has in fact in a great measure secured the understanding of the whole of the ideas contained in it. But instead of one question, the catechetical exercise has the power of originating many, each producing successively similar results, but with greater ease to the child, and with much more effect in rivetting the several ideas upon the memory. The first question, when properly put, gives the pupil the command of the whole proposition; but it requires considerable mental effort in the child to recall the words, and internally to translate the ideas for the first time. But when this has once been done, and a second question is asked from the same sentence, the ideas being now more familiar, there is less mental labour required in preparing the answer, and there being equal success, there is of course more satisfaction. The ideas become much more clear and distinct before the mind by a second review; and the effect, in fixing the whole upon the memory, is much more powerful than it could be by means of the first. When therefore the teacher confines himself to the original sentence, and does not indulge in catechetical wanderings, the questions, "When did God make all things?" "How many things did God make?" "Of what did God make all things?" and, "Why did God make all things?" produce extensive and powerful effects. The pupil finds himself able to master each question in succession without difficulty, and the answering of each appears to him a triumph. Whoever has been in the habit of making use of this exercise in the manner explained above, must have witnessed with pleasure the life, and energy, and delight, which it invariably infuses into the scholar, giving education a perfectly different aspect from what it usually assumes in the eyes of the young, and making it even in the estimation of the pupil a formidable rival to his play. In this manner has Nature set her seal upon this exercise, as a near approximation to her own process for attaining the two preparatory objects she has in view in the education of the young; that of cultivating the powers of the mind, and that of communicating to her pupils the elements of knowledge.

This exercise has been reduced to a regular system, which has placed it more directly at the command of all who undertake the instruction of the young. By a little attention on the part of parents and teachers, to a few simple rules, they may catechise upon any book, and apply the exercise to any species of knowledge whatever. We shall endeavour to explain the nature and uses of these rules.

For the purposes of this exercise, the school books of the pupil are supposed to consist of sentences, each of the principal words in which conveys some specific idea;—these again are combined into clauses, which also convey an idea;—and the combination of these clauses in a sentence, or paragraph, usually forms a complete truth. For example, the sentence, "God at first [made all things] of nothing [to shew his greatness,">[ contains one great truth; but the sentence which conveys it, embodies at least two clauses, inclosed in brackets, while the whole is made up of words, each of which is the sign of an idea which may readily be separated from all the others. Now it is evident, that questions may be formed by the teacher relative to each of these three parts. He may ask a question, which shall require the whole truth for the answer; or one which will be answered by a clause; or another which is answered by a word.

In "revising," accordingly, where time is an object, the teacher confines himself to those general questions which bring out the whole truth at once, as is exemplified in the Larger and Shorter Catechisms. This is called the "Connecting Exercise," because it is employed in uniting sections together, which have previously been taught to the pupils separately, but which are necessary to be perceived also in connection. This, however, would be too limited an exercise for the purpose of directing the mind to the several parts of a truth for the first time; and therefore the teacher in those cases forms his questions chiefly upon the clauses in the sentence, and the other words which have some material relation to them, and this is called the "General Exercise." But even this is not enough, where the child is dull, or where healthful mental exercise is required; and accordingly in that case, the teacher not only questions upon the clauses in connection with the other principal words, but he takes the words, of which the clauses are composed, and catechises the child upon them also. This is called the "Verbal Exercise," which has been found of great value in the teacher's intercourse with his younger classes. Upon these principles the Initiatory Catechisms and their Keys have been formed, together with the several Helps for communicating Scriptural knowledge. The success of these school books, although labouring under all the disadvantages of new instruments, imperfectly formed to work out new principles, is mainly to be attributed to the close imitation of Nature aimed at in all their exercises.